Textile treating process



United States Patent 3,488,139 TEXTILE TREATING PROCESS William J.Vullo, Tonawanda, N.Y., assignor to Hooker Chemical Corporation, NiagaraFalls, N.Y., a corporation of New York No Drawing. Filed Apr. 18, 1966,Ser. No. 543,056 Int. Cl. D06m 13/10, 13/26 U.S. Cl. 8120 9 ClaimsABSTRACT OF THE DISCLOSURE A method for imparting improved wrinkle andcrease resistance to textile materials by treating the materials withreaction products of neutralized tetrakis (a-hydroxyalkyl) phosphoniumhalides and epichlorohydrin. The textiles so treated are also claimed.

This invention relates to textile materials having improved wrinkle andcrease resistance and to the method of preparing such textile materials,and more particularly it relates to the treatment of textile materialswith organic phosphorus compounds so as to impart improved wrinkle andcrease resistance to the textile materials.

It is known that organic phosphorus compounds, useful in treatingtextile materials, may be prepared by the reaction oftris(hydroxymethyl)phosphine and epichlorohydrin. The properties oftris(hydroxymethyl)phosphine, however, make it difiicult to use, thematerial being readily oxidized during normal handling in air.Accordingly, in the general use of this material an inert atmospheremust be employed. For this reason, in the past, little use has been madeof such organic phosphorus materials in the treatment of textilefabrics.

It is, therefore, an object of the present invention to provide animproved method for treating textile fabrics so as to improved theirwrinke and crease resistance.

-A further object of the present invention is to provide a textilefabric having improved wrinkle and crease resistance.

These and other objects will become apparent to those skilled in the artfrom the description of the invention which follows.

Pursuant to the above objects, the present invention includes a methodfor treating textile materials to improve their "wrinkle resistancewhich comprises contacting the textile material to be treated with atreating solution containing the reaction product of a neutralizedtetrakis- (hydroxyalkyl)phosphonium halide and epichlorohydrin. Incontacting the textile material with this treating solution impregnationof the textile with the solution is effected and, thereafter, theimpregnated textile material is cured to produce a wrinkle resistanttextile fabric.

Textile materials which may be modified to improve their wrinkle andcrease resistance in accordance with the present invention include thosecomprising natural and synthetic polymers and blends of the same,possessing functional groups such as hydroxyl, amino, amido, carboxyl,thiol, and the like. Suitable polymeric materials include, for example,cellulosic materials, such as cotton, linen, paper and rayon, andproteinaceous material such as wool and silk. The textile materialstreated may be in any convenient form, such as fibers, threads, yarn,Woven fabric, non-woven fabric, knitted fabric and the like.Additionally, at the time of treatment, the fabric may be in theunfinished state or it may have been previously bleached, dyed, printed,or otherwise treated.

More specifically, in the practice of the present invention, the textiletreating composition is formed by reacting epichlorohydrin with aneutralized tetrakis(x-hydroxyalkyl)phosphonium halide. Preferably, thetetrakis(hy- 3,488,139 Patented Jan. 6, 1970 droxyalkyl)phosphoniumhalide is the chloride or bromide wherein the alkyl substituent is alower alkyl containing from 1 to 4 carbon atoms and, more preferably,the reactant is tetrakis(hydroxymethyl)phosphonium chloride. This lattermaterial is commercially available, typically as an aqueous solution. Itcan be safely and conveniently handled in air, either as a crystallinesolid, having a melting point of about centigrade, or as an aqueous ornonaqueous solution. Other suitable phosphonium halides which may beemployed include tetrakis(hydroxyethyl)phosphonium chloride, tetrakis(hydroxybu tyl)phosphonium bromide,tetrakis(hydroxypropyl)phosphonium chloride, and the like.

The phosphonium halide material is neutralized by reaction with a base,the base preferably being present in substantially equal molar amountswith the phosphonium halide. In this regard, it is to be noted thatalthough the preferred ratios of base to the phosphonium halide arebetween about 0.7 to 1.5, variation in these ratios is permissible andratios ranging from less than 0.1 to greater than 5, may be used in someinstances. As has been noted, however, the efiiciency of the subsequentreaction, with the epichlorohydrin in terms of yield, appears todecrease when ratios below about 1 are employed and, further, noadvantage has been found to be gained through the use of extremely highratios, such as those greater than 1.5.

Exemplary of the basic materials which may be used are alkali metalhydroxides, oxides, carbonates, tertiary amines, quaternary ammoniumcompounds, and in genera1, any strong base which is capable of forminghydroxide ions in aqueous solution. In many instances, the alkali metalhydroxides, and particularly sodium hydroxide and potassium hydroxidehave been found to be preferred. Accordingly, hereinafter, primaryreference will be made to these materials.

The neutralization of the phosphonium halide may be carried out ineither aqueous or nonaqueous medium. Suitable mediums include water;nonaqueous liquids such as methyl alcohol, ethyl alcohol, isopropylalcohol, dimethylformamide, acetonitrile; and mixtures of water and anon-aqueous liquid. Preferably, an aqueous medium is employed. Followingthe neutralization of the phosphonium halide with the base, theepichlorohydrin may be added to the neutralized material, the reactionbeing carried out in the same reaction medium as the neutralizationreaction.

Although the reaction of the phosphonium halide and the epichlorohydrinmay be carried out using substantially equal molar amounts, in :mostinstances it is preferable that the molar ratio of epichlorohydrin tophosphonium halide is at least about 3:1. Molar ratios ofepichlorohydrin to the phosphonium halide as high as 8 or more may beused, if desired, although in most instances, the results obtained havenot been found to be appreciably different than when using the lowerpreferred mole ratios, i.e., those of at least about 3 moles ofepichlorohydrin to 1 of the phosphonium halide.

The reaction between the phosphonium halide and the epichlorohydrin isexothermic and, generally, it has been found to be desirable to controlthe reaction temperature, preferably below about 50 centigrade. By socontrolling the temperature, too vigorous a reaction is avoided, withthe possibility of volatilizing the reaction components and causingundesired side reactions. The temperature control of the reaction may beconveniently carried out by utilizing a relatively slow addition ratefor the reactants or by cooling the reaction mixture, e.g., in an icebath.

Once the reaction product of the epichlorohydrin and the neutralizedphosphonium halide has been prepared, it

has been found to be preferable that this material is aged for at leastseveral days, and preferably for 3 to 4 weeks, before being used totreat the textile materials. Desirably, this aging is carried out atroom temperature, e.g. about 20 centigrade. Following the aging, thereaction product may be formulated into the desired textile treatingcomposition. Any suitable formulation may be used, for example, anemulsion, or a solution, with solutions being generally preferred. Thesolution may be applied by dipping, spraying, rolling, padding or thelike techniques, as are known to those in the art.

Following the application of the treating formulation, so as toimpregnate the textile material therewith, the excess of the formulationmay be removed by squeezing, centrifuging, pressing, or other similaroperations. The material may, if desired, be dried, and is then cured byholding the treated textile material for less than a minute at elevatedtemperatures to several hours at room temperature. In most instances,the curing is desirably carried out over shorter periods of time usinghigher temperatures. Although the use of an aqueous solution fortreating these textile materials is preferred, the reaction product maybe used as an emulsion, or as a solution in a suitable non-aqueoussolvent, such as alcohol, acetone dioxane, dimethylformamide, and thelike, or as a mixture of such non-aqueous solvent and water.

In formulating the textile treating composition, theepichlorohydrin-neutralized phosphonium halide reaction product isdesirably included in the formulation in amounts within the range ofabout 1 to about 50% by weight of the composition and preferably inamounts within the range of about to 40% by weight of the totalcomposition. Additionally, it has been found to be desirable to alsoinclude in the composition a catalyst, either a basic catalyst or anacidic catalyst. Such catalyst is desirably contained in the compositionin amounts within the range of about 0.1 to about 30% by weight of theformulation and preferably in amounts within the range of about 0.5 to20% by weight of the treating composition.

Suitable basic catalysts which may be used include the alkali metalhydroxides, alkali metal carbonates, alkali metal bicarbonates, alkalimetal acetates, alkali metal phosphates, alkali metasilicates,tetraalkylammonium hydroxides as well as other compounds which, whenadded to water, will increase the pH to greater than about 7.0. Of thesebasic catalyst, in many instances the preferred catalyst has been foundto be the alkali metal hydroxides, and specifically sodium hydroxide andpotassium hydroxide.

In addition to these basic catalysts, acidic catalysts may also be used.Exemplary of acidic catalysts which are suitable are hydrochloric acid,complex fluorine compounds, including the borofluorides, such as zincfluoroborates and the like. Generally, where such acidic catalysts areused, it is preferable that they are present in the solution in amountswhich will provide a pH within the range of about 4-6. It will beappreciated, however, that in some instances, the catalyst material maybe applied, in a separate step to the textile material either before orafter the application of the epichlorohydrin reaction product of thepresent invention. Generally, however, it has been found to bepreferable to include the catalyst in the epichlorohydrin treatingsolution, thereby applying both materials simultaneously.

The textile treating formulations are applied so as to provide on thetextile material an add-on desirably within the range of about 1 toabout 30% by Weight of the textile material and preferably within therange of about 2 to about by weight, after the treated fabric has beencured. It is to be appreciated, that the term add-on refers to themodifying agent which has reacted with the textile material, that is,the modifying agent which remains as an integral chemical part of thematerial after curing and washing to remove any unreacted excess. Theamount of add-on is given in percent by weight based on the original dryweight of the textile material.

The curing of the treated textile material is carried out by holding thematerial at temperatures between about room temperature, i.e., about 20centigrade, and about 250 degrees, centigrade, for a period of timesufiicient to permit the reaction between the textile material and theepichlorohydrin-neutralized phosphonium halide compound to take place.This period of time may range from several hours, where roomtemperatures are used, to less than 1 minute at elevated temperatures.Desirably, the curing is carried out at temperatures within the range ofabout 120 to 25 0 degrees centigrade, and preferably at temperatureswithin the range of about 150 to 185 degrees centigrade. At thesetemperatures, curing times of from about 10 to 25 minutes are typical.

If desired, the treatment with the textile treating formulation of thepresent invention may be supplemental by treatment with a hand modifieror builder, softener, waterrepellent agent, dyestutf or other materialwhich may further enhance Wrinkle resistance or impart or improve otherdesirable properties in the fabric. Such additional modifying materialsmay be applied simultaneously with the compounds of the presentinvention or they may be applied to the fabric before or after theapplication of these materials, in a separate operation.

In order that those skilled in the art may better understand the presentinvention and the manner in which it may be practiced, the followingspecific examples are given. In these examples, unless otherwiseindicated, temperatures are in degrees centigrade and parts and percentsare by weight. It is to be appreciated, however, that these examples areintended merely as being exemplary of the present invention and are notto be taken as a limitation thereof.

EXAMPLE 1 119 grams of an aqueous solution of tetrakis(hydroxymethyl)phosphonium chloride was placed in a reaction vessel. The vessel wasflushed with nitrogen and thereafter, 60 grams of a 10% aqueous solutionof sodium hydroxide was added to the reactor with stirring. After theaddition of the sodium hydroxide solution, the pH of the reactionmixture was within the range of 6.5 to 7. 153 grams of epichlorohydrinwas then added to the reaction vessel, the addition being carried outover a period of about 60 minutes. During the addition of theepichlorohydrin, the reaction vessel was maintained at a temperatureWithin the range of 40 to 55 degrees centigrade. Following the additionof the epichlorohydrin, the reaction mixture was stirred for 5 hoursunder a nitrogen atmosphere. The analyses of the reaction mixture showedthe presence of 2.43 moles of formaldehyde per mole oftetrakis(hydroxymethyl) phosphonium chloride and additionally showed theretention of 72% of original phosphorus in the material in oxidizableform. Thereafter, the reaction mixture was maintained in a closedcontainer for three weeks, at room temperature, At the end of this timeit was noted that the mole ratio of formaldehyde to the phosphoniumchloride had risen to about 2.67.

EXAMPLE 2 A textile treating bath was made by combining 30 parts of thereaction mixture of Example 1 with 3 parts of zinc fluoborate. Dilutehydrochloric acid was then added to this mixture to lower the pH toabout 5. Sufficient water was then added to make a total of parts oftreating solution. Swatches of bleached, desized, mercerized, 80 x 80(threads per inch) cotton print cloth weighing 3.1 ounces per squareyard were then padded through this solution and a wet pickup on thefabric of 86% was obtained. After drying, the treated fabrics were thencured for 15 minutes at 150 centigrade and then washed in a hot /2%aqueous solution of detergent, given a hot water rinse, and iron presseddry. The add-on on the fabric was 6.34%. A determination of the wrinklerecovery angles, using the Monsanto method, showed recovery angles inthe fill direction of degrees, dry, and

degrees, wet, as compared to 72, dry and 89, Wet for an untreatedcontrol. The treated fabrics were then bleached in a hydrochloritesolution and heated for 30 seconds at 185 centigrade. Examination of thefabric after the treatment showed no evidence of scorching and thefabric remained white in color. Additionally, the application of a matchflame to a strip of the cloth, held vertically above the match showed amuch slower burning rate for the treated sample than for an untreatedcontrol and the treated sample showed no evidence of afterglow, whereasconsiderable afterglow was present in the untreated control.

EXAMPLE 3 The procedure of Example 2 was repeated, with the exceptionthat the pad bath for treating the textile fabric contained 30 parts ofthe product of Example 1, parts of a 10% aqueous solution of sodiumhydroxide, and 40 parts of water, to make a total of 100 parts oftreating solution. Fabric treated with this pad solution, in accordancewith the method of Example 2, gave an add-on of 6.05% after curing,washing, and drying. Additionally, the cloth had a wrinkle recoveryangle, in the fill direction, of 119 degrees, dry, and 129, wet, ascompared to recovery angles of 72 degrees, dry, and 89, degrees, wet,for an untreated control. After bleaching, and heating, the treatedsamples remained white in color and showed no evidence of scorching.When subjected to a match flame, as in Example 2, the treated fabricburned appreciably more slowly than an untreated control and showed noafterglow, whereas, the untreated control had appreciable afterglow whenthe flame of the burning cloth was extinguished.

Following the general procedure of the above examples, when thetetrakis(hydroxymethyl)phosphonium chloride in Example 1 is replaced byequal molar parts of tetrakis(hydroxyethyl)phosphonium chloride;tetrakis (hydroxybutyl)phosphonium bromide; andtetrakis(hydroxypropyl)phosphonium chloride, and the resulting reactionproducts are used for treating textiles in accordance with theprocedures of Examples 2 and 3, similarly wrinkle resistant fabrics areobtained.

What is claimed is:

1. A method of imparting improved wrinkle and crease resistance totextile materials having functional groups capable of reacting withadducts of epichlorohydrin and neutralized tetrakis (a-hydroxyalkyl)phosphonium halide, which comprises:

(A) impregnating said textile material at a pH of at least about 4 withfrom about 1 to about 30 percent by Weight of the reaction product of(1) epichlorohydrin and (2) a neutralized tetrakis (oz-hydroxyalkyl)phosphonium halide produced by reacting a tetrakis (a-hydroxyalkyl)phosphonium halide with from about 0.1 to about 5 moles per mole of saidphosphonium halide of a basic compound capable of forming hydroxyl ionsin aqueous solution; said reaction product of epichlorohydrin andneutralized tetrakis (a-hydroxyalkyl) phosphonium halide produced byreacting epichlorohydrin with said neutralized phosphonium halide in amolar ratio of from about 1:1 to about 8:1 at a temperature of fromabout 0 to about 50 degrees centigrade, and

(B) curing said impregnated textile material at a temperature of fromabout 20 to about 250 degrees centigrade.

2. The method as claimed in claim 1 wherein the reaction product withwhich the textile material is treated is the reaction product of aneutralized tetrakis(hydroxy rnethyl)phosphonium chloride andepichlorohydrin.

3. The method as claimed in claim 2 wherein the curing of the treatedtextile material is carried out by heating the material at a temperatureWithin the range of to 250 centigrade.

4. The method as claimed in claim 3 wherein the textile material treatedis a cellulosi'c textile material.

5. The method as claimed in claim 4 wherein the formulation with whichthe textile material is treated also contains a basic catalyst presentin an amount of from about 0.1 to about 30 percent by weight of theformulation.

6. The method as claimed in claim 4 wherein the formulation with whichthe textile material is treated also contains an acidic catalyst presentin an amount of from about 0.1 to about 30 percent by weight of theformulation.

7. An improved textile material consisting essentially of materialhaving functional groups selected from the group consisting of hydroxyl,amino, amido, carboxyl and thiol, impregnated with from about 1 to about30 percent by weight of the reaction product of epichlorohydrin and aneutralized tetrakis (u-hydroxyalkyl) phosphonium halide.

8. The textile material as claimed in claim 7 wherein the reactionproduct is the reaction product of neutralizedtetrakis(hydroxymethyl)phosphonium chloride, and epichlorohydrin.

9. The textile material as claimed in claim 8 wherein the material is acellulosic textile material.

References Cited UNITED STATES PATENTS 2,668,096 2/ 1954 Reeves et al.2,993,746 7/1961 Miles et 'al. u 8-116 3,054,698 9/ 1962 Wagner 117l36MAYER WEINBLA'I'I, Primary Examiner US. Cl. X.R.

